This application claims the benefit of Korean Patent Application No. 2001-0068510 filed on Nov. 5, 2001, in Korea, which are both hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a method and system of monitoring a plasma process chamber, and more particularly, to a method and system that prevent an arcing in the plasma process chamber during a plasma process.
2. Description of Related Art
In a plasma process used for fabricating semiconductor devices, a high frequency power is applied to a process chamber to generate the plasma. At this time of applying the high frequency power, if the process chamber is electrically floated (not grounded), the process chamber will be charged up by the applied high frequency power. The charged ion species in the process chamber threaten the operator and cause the unstable operation of the process chamber. Thus, the process chamber is generally grounded. Especially, the ground line connected to the process chamber has low impedance.
If the charged ion species in the process chamber do not leak properly, micro-arcing occurs between the generated plasma and the charged ion species. Furthermore, the charged ion species will cause the micro-arcing in the bad connection part of the ground line. In case of producing the micro-arcing, the plasma generated in the process chamber do not have stability; the plasma process conducted in the process chamber is not trusted; the expected life span of the process chamber and other devices will be shortened; and the operator conducting the plasma process devices may be harmed.
Therefore, a new method and system have been required to prevent the occurrence and frequency of the arching caused by the charged ion species in the plasma process chamber.
Accordingly, the present invention is directed to plasma process chamber monitoring method and system that substantially overcome one or more of the problems due to limitations and disadvantages of the related art.
An advantage of the present invention is to provide a method and system of monitoring a plasma process chamber in order to prevent arcing caused by charged ion species.
Additional features and advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a method of monitoring a plasma process chamber in which fabricating a semiconductor device is conducted using a plasma includes grounding the plasma process chamber using a ground line; detecting a current flowing in the ground line from the plasma process chamber to the ground; interpreting whether said current is more than a reference value during fabricating the semiconductor device; and deciding that the plasma process chamber is in an abnormal state when said current is more than the reference value.
In order to accomplish the above advantages, in another aspect, the principles of the present invention provide a system of monitoring a plasma process chamber. The system includes a plasma process chamber which is grounded by a ground line and in which a semiconductor device fabrication is conducted; a current detecting sensor detecting a current flowing in the ground line from the plasma process chamber to the ground; a programmable logic controller (PLC) connected to the current detecting sensor, wherein the PLC provides an abnormal signal output when the current detected by the current detecting sensor is more than a reference value and a normal signal output when the current detected by the current detecting sensor is less than the reference value; and a central controlling computer connected to the PLC, wherein the central controlling computer interprets the abnormal signal as the plasma process chamber is in an abnormal state, outputs an alert signal through a warning system, and shuts off a high frequency power that is applied to the plasma process chamber to generate the plasma when the central controlling computer receives the abnormal signal from the PLC. In the present invention, the current detecting sensor is a current transformer (CT) or a current detector. The reference value is 1 ampere (A).
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.